Piston ring



June 26, 1928. 1,675,109

R. V. KELLY PISTON RING Filed May 21., 1927 A T.TORNE Y.

Patented June 2c, 1928.

. UNITED STATES 1, 75,109 PATENT oFFIcE.

RALPH V. KELLY, OF DETROIT, MICHIGAN.

' PI$TON RING.

- Figure 1 is. an elevation of a piston having single rings in its uppergrooves and showing two coaxial rings in the lower groove.

Figure 2 is a section on the line II, II, Figure 1.

Figure 3 is a plan view to an enlarged.

scale of a portion of a ring and the adjal5 cent spring, together with adiagram illustrating the construction of these parts.

Figure 4 is a detail section on the line IV, IV, Figure 1. Figure 5 is adetail section on the line V, 2 V, Figure 1 Figure 6 is a detail planview of a portion of a ring and adjacent portion of the pressure ringshowing a modified construction.

a is a piston having the ring grooves b, b therein. a'represents thesingle ring in an upper groove 6. 0 and. 0 are the rings constitutingthe double ring in the lower groove. (2 is the split separating the endsof the ring 0 and d d indicates the similar splits in the rings 0 0 I cis a hexagonal springwith its corners rounded, as hereinafter described.The ends of this spring are separated by the slot 6 0 indicates each ofsix grooves formed at equal intervals in the inner surface of the ring0.

The grooves c are arcs of circles in the plane of the ends of the samelength of radius, as for instance the radii of circles whose centers areupon radii of the ring 0 and upon a circle r0 Figure 3, concentric withthe ring '0. The rounded corners 6 ofthe spring e are also arcs ofcircles, the radii of which are on the radii of the ring 0 and upon acircle re Figure 3, concentric with the ring 0 and of less diameter thanthe circle r0 so that the radii of the arcs of the spring are less thanthe radii of the arcs of the groove 0. The rounded corners e ofthespring 6 bearing the grooves c in the inner surface of the ring 0, asshown. The split in the ring comes at a groove of in which the spring eis contin- I uous and the split in the spring e comes in a groove 0 ofthe ring a, the walls of which are continuous. The corners of the spring6 are connected by approximately straight portions which bear at theircenter against the Application filed May 21,

1927. Serial N6. 193,132.

bottom of the piston groove, as shown at a.

By this construction I obtain a broad bearing surface for the corners e?of the spring a so that the spring does not wear as rapidly at thesepoints of contact. The arcs of the outer surface of the spring cornerhaving only slightly less curvature than the surface of the groove 0". Ialso obtain more room for the functioning of the spring 6 between thebottom of the piston and the inner surfaceof the ring 0. A roundedcorner 6. fits into a groove 0 where the ring 0 is divided and coversupthe slot that separates theends of the ring so as to prevent leakagethrough the slot. Where two rings are employed, as 0' 0 Figure 5, theengagement of the corners e in theslot .9 hold thetwo rings fromrelative angular movement, so that the opening' d, d between the endsof. said ring cannot come together. The grooving of the ring 0 makesthesame more flexible so that it will more easily adapt itself to theshape of the cylinder and respond more perfectly "to the pressure of thespring 6, while practically retaining its strength and wearingqualities.

While have shown and described a hex ago'nal spring and a correspondingconstruction of the ring, of course any number of corncrs may beemployed and the ring grooved to correspond. I

' In Figure 6 I have'shown a modified construction in which the groove 0in the piston ring and the contiguous portion of the spring havegthesame radius of curvature. In this casethe ringis rounded off at c wherethe curvature of the groove meets the curve of the interior surface ofthe ring.

What I claim is: 1'. The combination of a ring having a vertical groovein its inner surface and a ners, said ring. being provided with verticala grooves in its inner surface, said corners of the spring being shapedto the surfaces of said grooves and engaging therein.

4. The combination of a piston having a.

' ring groovetherein, a ring in said groove, a.

the surface of said groove and engaging in said groove, said ring beingcut through at the poiht of engagement of the surface'of said spring 6.The combination of two split rings 1ying one upon the other so that thesplit in vertical grooves in the inner surface of said rings and a.pressure ring engaging in both of said grooves. s

7. In a piston ring construction the combination of a ring havingarcuate grooves in its inner surfacesspaeed from. each other around saidring making the ring thinner where said "grooves'are formed and apressure spring engaging in-each of said grooves, said spring having anarcuate surface of somewhat greater curvature than said groove.

In testimony whereof, I sign this speoiv fication.

RALPH- V. KELLY. e

